Many industries offer highly variant products to their customers, a prime example being the automotive industry. Automobile manufacturers typically offer several models to their customers, who can often choose among numerous options for a selected model. As a result, it becomes necessary for a manufacturer to keep track of hundreds of products and their corresponding component structures and related production processes. Manufacturing companies offering a high variance of products and wishing to maintain reasonable costs depend on an efficient information system for products and their associated components and processes.
Existing database systems for product structures tend to be redundant. For example, a database may contain component lists for hundreds of different products, the result being that the same component would be listed separately for each product with which it is associated. While such a system may be useful for manufacturing products, it is impractical from a design perspective. A designer cannot readily view, for example, the extent of specific products or product classes affected by a change to a particular component. Nor could he easily obtain a clear picture of which components are common to certain product classes, and which are specific only to a particular product within a class. Nor could he see the routing a particular product and its components through its production processes. These are important features from a cost perspective, since they enable a designer to make decisions as to whether or not to include, or to change, particular components based on the number of products or product classes that are affected. An accurate view of the components and processes associated with product classes is vital for efficient design and manufacturing.
A system for depicting products and their associated components was described at a presentation given by Volkswagen at the CIMData European Conference in 1997. The system includes a data structure with a tree-like representation of the various components and subcomponents for a single model of a car. Each component is represented by a node and is associated with specific variants, such as "leather" and "vinyl" for the component "seat". The structure is limited to a single product class, however. Since there is no product hierarchy, components are mapped to at most one product class. Therefore, the system does not enable alternative viewing of components associated with broad product classes and components associated with particular products, as would be desirable both from design and production perspectives, respectively.
Another example of a system for depicting a similar structure is the STEP Protocol ISO 10303-214. Although this system can depict the processes as well as components for a particular product class, it does not distinguish between the actual production steps required for a general process, and those steps required for specific processes. Accordingly, the system cannot accurately maintain or display the actual production steps required for production of a particular product variant. Furthermore, STEP does not enable viewing of components and processes associated with different product classes, nor does it allow for more than one possible decomposition of a particular component.
It would be desirable to have a computer based system containing a hierarchy of product classes, whereby individual product components are mapped to all product classes with which the component is related, and all components of a particular product class can be displayed in a graphical format. Specific component variants, representing the concrete item used for a particular product variant, would also be associated with each component. Similarly, the processes required to assemble components would be mapped to those components, and specific variants of those processes, or the actual production steps associated with particular component variants, associated with each process. The computer based system would enable viewing of all of the components and processes associated with any product class within the product class hierarchy on a display.